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päääd - Hack.lu CTF 2023

alfin
2023-10-16
Web

tl;dr

  • meta redirect to attacker website, using the html injection in the paaad.
  • leak the unique subdomain with csp violation.
  • Another meta redirect csrf with the leaked subdomain to make the note public.
Read More
Hack.luCTF2023

Awesomenotes II - Hack.lu CTF 2023

Z_Pacifist
2023-10-16
Web

tl;dr

  • XSS + HTML sanitization library (ammonia) bypass
  • Namespace confusion in ammonia using custom allowed extra tags(math & style)
Read More
Writeup Web mXSS Hack.lu CTF 2023

0_CSP - Securinets-Quals 2023

Lu513n
2023-08-07
Web

tl;dr

  • CRLF Injection in Headed Key in Werkzeug headers.set
  • Using CRLF Injection at /?user= to Get XSS at /helloworld
  • Make the admin visit /?user=<PAYLOAD> and /helloworld using cache poison or bug in regex(uninteded)
Read More
Securinets-Quals CRLF XSS Cache-Poison

Another Secure Store Note - LINE CTF 2023

ma1f0y
2023-03-28
Web

tl;dr

  • Leak csrf token bypassing document.domain
  • visiting /profile/ will not change the nonce
  • Leak nonce using dangling markup in firefox
  • Add XSS payload using the csrf to get the flag
Read More
LINECTF2023

Vessel Cartographer - HTB CyberApocalypse 2023

retr0ds
2023-03-24
Reversing

tl;dr

  • Dynamically resolved hashed API
  • Tls_call_back based anti-debug check
  • AntiDebugFlag check implemented using ProcessInformationClass
  • AES_CBC decryption of image to find flag
Read More
Writeup HTBCA23 Reversing AES_CBC

valentine - hxpCTF 2022

sk4d
2023-03-15
Web

tl;dr

  • SSTI in the valentine card
  • bypass filter by setting ejs delimiter option
  • RCE :yay:
Read More
hxpCTF

sqlite_web - hxpCTF 2022

ma1f0y
2023-03-14
Web

tl;dr

  • Create a sqlite3 extension with rce payload.
  • Abuse werkzeug tempfile to upload the extension to server.
  • load that extension using load_extension(‘/proc/self/fd/fd_no’);
Read More
hxpCTF

cs2100 - HackTM CTF Quals 2023

k1R4
2023-02-23
Pwn

tl;dr

  • LOAD and S_TYPE opcodes lead to OOB when addr > DRAM_BASE+DRAM_SIZE
  • Get libc and stack pointers and offset to obtain RIP offset and base
  • Write ropchain on stack using libc gadgets
  • Perform ORW on flag file
Read More
Exploitation VM

BlueLock - bi0sCTF22

AmunRha
2023-02-10
Reversing / Windows

tl;dr

  • Implemented two SEH and two VEH Exception Handlers
  • Two stage malware challenge with process injection technique
  • CPP binary where logic is wrapped in classes and their member functions
Read More
bi0sCTF Windows Reversing ExceptionHandling

scorescope - DiceCTF 2023

sk4d
2023-02-07
Web

tl;dr

  • read output using ValueError
  • sys.modules to print all the app modules
  • go through the module classes and find the test case functions and re-write them to always return true
Read More
DiceCTF2023

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